OTA firmware updates on ESP32 based microcontrolers

The Over-the-air update mechanism is really important for managing and maintaining the firmware of Internet of Things devices deployed in the field. This paper explores the implementation of over-the-air updates for ESP32 microcontrollers using the Espressif library, focusing on three distinct wireless communication protocols: Wi-Fi via HTTPS, Bluetooth Low Energy, and Zigbee. The study presents an approach to understand these protocols for firmware updates. We discuss the architecture and steps involved in configuring and executing over-the-air updates over Wi-Fi, which is the most commonly used protocol for such operations. Additionally, we explore the implementation of over-the-air updates via Bluetooth Low Energy, highlighting the constraints and advantages of this low-power communication method. Furthermore, the paper addresses over-the-air update strategies using Zigbee, a protocol tailored for low-power, mesh network environments, with concept of fully automated update system and fault detection algorithms for improving versioning system.